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Experts Recommend Keeping Hubble Operational
foolishtook writes "
The New York Times is reporting that a panel of experts is recommending NASA to keep the Hubble Space Telescope operating past 2010 when its replacement, the James Webb Space Telescope, is currently slated for launch. NASA had stated that it wanted to bring the Hubble down in 2006 to make room in its budget for the Webb, but astronomers said that it still has a viable future and the launch date for the Webb is likely to be delayed."
I heard a piece on NPR about this yesterday. They said that there were three options, one was to send two more maned space missions to the hubble for repares and to attach a propulsion system to the unit so that it can safely be brought back to earth in 2010. The second was to go along with the current plan, send one more maned mission, that will do some minor upgrades and bring hubble down in 2006. The third option is to not send any more maned missions, and develop a robotic device that could be sent up and would attach the propulsion system to the unit.
NASA said that it was worried about sending more maned missions up to the hubble since it is in a different orbit than the space station and if the mission is botched the shuttle would not be able to reach the station in an emergency.
Visualize the world of wine
Experts Urge a Reprieve for the Hubble Space Telescope By DENNIS OVERBYE he Hubble Space Telescope, astronomy's vaunted time machine, was granted a conditional reprieve yesterday when an expert panel recommended that NASA consider sending a crew of astronauts at the end of the decade to extend its career, rather than dropping it out of orbit, as has been planned.
But the committee said its recommendation should be carried out only if the science to be performed in those additional years was able to beat competing proposals for new NASA science projects.
For the last 13 years, floating above the Earth's murky atmosphere, the telescope has beamed down crisp images of galaxies still forming at the dawn of cosmic time, peering into the hearts of galaxies and quasars in search of black holes, and investigating the mysterious "dark energy" that seems to be wrenching the cosmos apart.
"By any standards the H.S.T. has been a spectacular success -- one of the most remarkable facilities in the entire history of science," said the committee, whose chairman is Dr. John Bahcall of the Institute for Advanced Study in Princeton, in a report posted yesterday on the Web site of the National Aeronautics and Space Administration.
The committee members and other astronomers pointed out, however, that since the breakup of the Columbia shuttle, the telescope's future has been threatened because it is hostage to the ability of a space shuttle to pay periodic visits for maintenance and to replace old instruments with new ones.
Those repair missions would take the shuttle too far from the orbit of the International Space Station in case of trouble. As a result, the space agency should be prepared for a range of possibilities, the report said, from no more shuttle missions to two.
More is likely to be heard on that score in a couple weeks when the report of the Columbia Accident Investigation Board is released. But ultimately, Dr. Bahcall said, Congress, the White House and the NASA administrator will decide whether the shuttle may visit the telescope.
Dr. Anne Kinney, who is in charge of astronomy and physics in the space agency's office of space science, said that the Bahcall committee's report was "a good report."
"It reminds us that we need to be flexible," Dr. Kinney said. But she added that there was no budget for the extra mission and no precedent for the kind of competition that Dr. Bahcall and his colleagues had proposed.
"It's going to be a challenge," she said.
Astronomers were generally pleased with the report. Dr. Wendy Freedman, director of the Carnegie Observatories in Pasadena, Calif., called it "balanced and thoughtful."
Dr. George Rieke, an infrared astronomer at the University of Arizona, said the idea of a competition was "a sensible way to deal with limited resources."
Dr. Steven V. W. Beckwith, director of the Space Telescope Science Institute, praised the report, saying, "I couldn't be happier."
He added:"Everyone here is tremendously grateful to NASA for its support of the Hubble. We're delighted to have the chance to compete to continue this extraordinary story."
The story of the $1 billion Hubble, launched in 1990, is one of the great comeback stories in modern science. It was designed to take advantage of an orbital vantage point above the Earth's atmosphere, which smears images and blocks some wavelengths of light from reaching ground-based telescopes.
Once it was in orbit, however, astronomers were devastated to discover that the telescope had a flawed mirror.
The flaw was corrected in 1993 by sky-walking astronauts who, in effect, fitted the telescope's instruments with corrective lenses, enabling Hubble to attain the glory for which it was designed.
NASA has long planned to end Hubble's spectacular run and bring it down to make way in the budget for the James Webb Space Telescope, now scheduled to be launched in 2011. But som
The flying hamster of DOOM rains coconuts on your pitiful city.
I'll have to check, but I don't think the Shuttles are made to bring such large objects down from orbit. The re-entry procedures are run virtually entirely by a computer which has the Shuttle's weight programmed into it and the Hubble, if not very heavy, would throw off the balance of the Shuttle and make it harder for the computer to correct for deviations. (This is what they said happened to the Columbia, the flight characteristics of the Shuttle changed too quickly for the computer to compensate and further worsened the damage.)
"Ford," he said, "you're turning into a penguin. Stop it."
I didn't see anything on the Hubble page linked above as to what it costs to keep the telescope in orbit. Other than a little maintainence, it can't be that much, can it? I know that a "little" is a relative term, but still. I'd say leave it up there for as long as possible.
Overrated / Underrated : Moderation
The Hubble was designed (and originally planned) to be returned with a Shuttle. But due to the latest happenings, that's been canned. It's too bad, since there would be plenty of science and engineering learned from reviewing the affects the environement had on the materials of Hubble.
~afniv
"Man könnte froh sein, wenn die Luft so rein wäre wie das Bier"
Richard von Weizs
Hubble can't look at the earth because it's too bright. Even the nightside has so much light (human illumination, moonlight, lightning) that the Hubbles photodetectors would saturate and be permanently degraded or destroyed. The Hubble does not have a neutral density filter, just a shutter to block all light during servicing or if the attitude control that keeps it from seeing earth, moon, or sun goes south.
Hubble Altitude = 370 statute miles
Space Station Altitude = 240 statute miles
Difference = Waaaaay too much.
"A microprocessor... is a terrible thing to waste." --
GeneralEmergency
Most observations are made over a long period of time. The vibrations transmitted from the ISS would make observations impossible. There's also probably quite a bit of junk around the ISS which could foul up the Hubble.
they should just keep the hubble working until it well, cant. dont decommision something that gives us as good pictures as these while it is still working.
-caf
Here's a link to a white paper (PDF format) prepared by the Space Telescope Science Institute's Scientific Staff with their input to NASA on why they feel Hubble's mission should be extended.
FYI: The cost to keep the Hubble in orbit and to maintain it is roughly 200 million a year.
No, this is far from the first mission to the Earth-Sun lagrange points. I know of at least two sat at L1 (between Earth and Sun), SOHO, a solar obervatory, and Genesis, a solar wind collector. There is also at least one at L2 (opposite side of Earth from Sun), MAP, a cosmic background radiation mapper.
All the stories about colonization of the lagrange points are the Earth-Moon points. I don't know if there have been any missions to these points, but that doesn't mean there hasn't been any.
Lots of technical and environmental problems are solved by the application of vast amounts of nuclear power
1) The IIS is low orbit, that means that every now and then you have to boost it back to higher altitudes. That is expensive (fuel) and expense increases with the load attached.
2) As for hauling the Hubble, it is on a much higher orbit, enough higher that it is not feasible, even if it was desirable
3) GPS sats are NOT geo-sync. Geo-sync sats are those that maintain the same position relative to a point in Earth's surface. The TV and comm sats are examples of those. Their orbits are all over the equator line, and several thousand miles high.
I seriously therefore doubt all the posts about the Earth, even the nightside of the Earth, being too bright for Hubble to image. Too bright? Reduce your shutter speed !
Also, one poster said the Earth is too close to focus on. Probably also incorrect. Remember the Hubble is ? a few hundred miles up ?. Typically with telescopes or camera lenses, the focus difference between "infinity focus" and "a few hundred miles" is non-existent. Not like the Hubble is exempt from being a telescope. As a matter of fact it's a Ritchey-Cretian telescope just like you can buy here on Earth from these dudes.
More specifically (from Celestrak)
Hubble: 28 degrees inclination
ISS: 51 degrees inclination
Exercise for the student: work out the required delta V (here's a useful reference). Compare with the Shuttle's on-orbit delta V. It's cheaper (and lots easier) to land and get a fresh launch.
...laura
This one?
Oh, give me a locus where the gravitons focus
Where the three-body problem is solved,
Where the microwaves play down at three degrees K,
And the cold virus never evolved.
(chorus)
We eat algea pie, our vacuum is high,
Our ball bearings are perfectly round.
Our horizon is curved, our warheads are MIRVed,
And a kilogram weighs half a pound.
(chorus)
If we run out of space for our burgeoning race
No more Lebensraum left for the Mensch
When we're ready to start, we can take Mars apart,
If we just find a big enough wrench.
(chorus)
I'm sick of this place, it's just McDonald's in space,
And living up here is a bore.
Tell the shiggies, "Don't cry," they can kiss me goodbye
'Cause I'm moving next week to L4!
(chorus)
CHORUS: Home, home on LaGrange,
Where the space debris always collects,
We possess, so it seems, two of Man's greatest dreams:
Solar power and zero-gee sex.
--Home on Lagrange (The L5 Song)
(C) 1978 by William S. Higgins and Barry D. Gehm
Laws do not persuade just because they threaten. --Seneca
You may be reading some articles stating that the Webb is the replacement for Hubble, but it simply isn't true.
a sp
Here is a quote from "Sky and Telescope":
"Three issues lie at the heart of the debate.
First, Hubble has unique capabilities for ultraviolet and visible-light astronomy that will not be replaced by any other planned mission for 10 to 20 years (Webb is designed mainly for infrared imaging and spectroscopy).
Second, Webb hasn't yet moved much beyond the drawing board and may not be ready for launch until the middle of the next decade, leaving astronomers with no space telescope at all for several years if Hubble shuts down by 2010.
And third, Hubble is more than just a telescope. "HST is widely recognized as an extraordinary scientific, educational, and inspirational national asset," wrote Garth Illingworth (University of California, Santa Cruz) and Michael Shull (University of Colorado). In other words, it is an icon."
Read more at:
http://skyandtelescope.com/news/article_1017_1.
"Music is everybody's possession. It's only publishers who think that people own it." - John Lennon.
TPF http://planetquest.jpl.nasa.gov/TPF/tpf_index.html l
SIM http://planetquest.jpl.nasa.gov/SIM/sim_index.htm
LISA http://lisa.jpl.nasa.gov/
It's a lousy idea.
Hubble has to be able to point with great accuracy and precision to a few milli-arcseconds for long periods of time. The vibrations of all the plumbing and fans necessary to sustain life on the ISS would kill its ability to look at it, even if you could get it there, and even if it could operate at 240 miles altitude and not 370 miles as it was designed (lots more atmosphere down there - contaminants).
ISS is at 240 miles, and it's damn hard to get the equipment and supplies necessary to support life there as is. Geosync is 22,000 miles, two orders of magnitude farther away, and this guy wants to put multiple space stations there with people hanging around to do occasional maintenance? Who is going to pay for that when it will be orders of magnitude cheaper just to send up another unmanned geosync satellite just like they do now?
Then, some day in the long run, you use these stations to assemble and launch real space-ships, ones that don't have to deal with the problems of getting to and from the bottom of a gravity well.
How does the material to make "real space-ships" get to the stations? From the bottom of a gravity well, I'd imagine. And why do you think that geosync isn't still at the bottom of a gravity well? You're in orbit! By definition you're still in the earth's gravity well!
Ahh, dreams...
Yeah, dreams don't usually have to obey the laws of orbital mechanics.
Why does this get moderated as "interesting"? There's literally not a single sentence in it that makes sense.
For those of you who dislike nytimes registration,
9 99 94061
here is the newscientist link:
http://www.newscientist.com/news/news.jsp?id=ns
Why do they stick more and more satelites into orbit when they're only going to ultimately fall back down to earth anyways?
A) The JWST is not going to be an Earth satellite. It will be placed at the L2 Lagrange point, which makes it more properly a satellite of both the Earth and the Sun. The L2 Lagrange point is very, very far away -- around a million miles from the Earth, and the JWST will have to travel for three months to get there.
B) It's not going to fall back to the Earth. It will drift off into space.
Here's a wild thought.... build these space telescopes right on the surface of the moon!
C) Here's a wild thought -- maybe the rocket scientists know more about this than you do! In this case, they can't put the JWST on the moon, because the temperature is far too warm (some of the JWST's sensors will operate at a mere 7 degrees Kelvin). Being in space also makes life a lot easier in other respects, as you don't have a rocky body blocking half your possible field of vision at all times.
ZFS: because love is never having to say fsck
According to NASA, in 2005 "Space Technology 3" is due to fly. It is a pair of formation-flying telescopes which will (hopefully) result in the first orbital stellar inferometer. The project website: http://nmp.jpl.nasa.gov/st3/proj/index.html
Let's hope for a more inspiring name between now and then.
There is currently an inferometric project underway at Keck, HI -- http://planetquest.jpl.nasa.gov/Keck/keck_index.ht ml
Bush Lies On the Record.
Actually, according to the Bad Astronomer, the Hubble is sometimes pointed at Earth, for some sort of calibration tests. The images it returns are utterly useless, though. The Earth moves so fast relative to Hubble that all the images consist of is a mess of blurry colors.
"To confine our attention to terrestrial matters would be to limit the human spirit." -Stephen Hawking